package com.moli.filter;

import com.alibaba.fastjson.JSON;
import com.moli.domain.ResponseResult;
import com.moli.domain.entity.LoginUser;
import com.moli.enums.AppHttpCodeEnum;
import com.moli.utils.JwtUtil;
import com.moli.utils.RedisCache;
import com.moli.utils.WebUtils;
import io.jsonwebtoken.Claims;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Objects;

/**
 * @Author： XC
 * @Date： 2023-06-08 10:04
 * @Description：
 */
@Component
public class JwtAuthenticationTokenFilter extends OncePerRequestFilter {

	@Autowired
	private RedisCache redisCache;

	@Override
	protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
		//1.获取请求头中的token
		String token = request.getHeader("token");
		//判断请求头中是否有token
		if(!StringUtils.hasText(token)){
			//说明该接口不需要登录  直接放行  由其他过滤器拦截
			filterChain.doFilter(request, response);
			return;
		}
		//2.解析获取userid
		Claims claims = null;
		try {
			claims = JwtUtil.parseJWT(token);  //解析
		} catch (Exception e) {
			e.printStackTrace();
			//token超时  token非法
			//响应告诉前端需要重新登录
			ResponseResult result = ResponseResult.errorResult(AppHttpCodeEnum.NEED_LOGIN);
			WebUtils.renderString(response, JSON.toJSONString(result));
			return;
		}
		String userId = claims.getSubject();
		//3.从redis中获取用户信息
		LoginUser loginUser = redisCache.getCacheObject("bloglogin:" + userId);
		//如果获取不到
		if(Objects.isNull(loginUser)){
			//说明登录过期  提示重新登录
			ResponseResult result = ResponseResult.errorResult(AppHttpCodeEnum.NEED_LOGIN);
			WebUtils.renderString(response, JSON.toJSONString(result));
			return;
		}
		//4.存入SecurityContextHolder
		UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(loginUser,null,null);
		SecurityContextHolder.getContext().setAuthentication(authenticationToken);

		filterChain.doFilter(request, response);
	}


}